The book is dedicated to Jeremy Safran, whose recent tragic loss drove the editor as well as the publisher to gather these contributions about enactment, a topic to whom Safran devoted many papers of his. The collection Borders of Psychoanalysis includes books that investigate an area of research that our publishing house wants to cover since its foundation: that of the dialogue of contemporary psychoanalysis with 'confining' disciplines (for example, neuroscience, infant research, cultural anthropology), often with epistemologies that for origin and history appear to be incomparable to it. As Safran wrote, though problematic and source of confusion among different psychoanalytic approaches, this epistemological status of psychoanalysis, related to its condition of 'liminality', is a meaningful source of vitality for the discipline (Safran, 2012). The book explores the subject of enactment in relation to boundaries in psychoanalysis, referring to a series of viewpoints that lead to many crucial areas. From an intra-psychic point of view, enactment can be studied at the between internal and external (world), psyche and soma, psychic apparatuses (first topic) and 'provinces' (second topic), primary and secondary process, perception and representation, representation and affect, Ego and object, subject and object (included the concept of 'transitional space' by Winnicott). At this level we have to consider that many authors who have take into account very profoundly enactment are those who questioned the linearity of classical Freudian topics (the continuity between unconscious, preconscious and conscious, interrupted only by repression and negation), considering dissociation as a key mechanism apter in order to reflect and account for a discontinuous model of psyche (Bromberg, 2014). From an inter-psychic point of view, enactment can be explored in relation to the concept of intersubjectivity and 'the third' (Aron, 2006; Benjamin, 2004) to indicate the functioning that affects the entire analytic pair at work. At this level we can place all the theories on boundaries of the analytic setting and the whole clinics of their violations. From an intra-disciplinary point of view (inside of psychoanalysis), enactment can be considered according to different currents of contemporary psychoanalytic thought. From an inter-disciplinary point of view, enactment can be viewed as a 'bridge' concept between psychoanalysis and the other 'confining' disciplines, especially psychiatry but also infant research and neuroscience. Moreover, it is to be added an inter-cultural point of view, from which enactment can be considered as a transitional concept allowing to enlight cultural counter-transference phenomena in transcultural clinical setting. Finally, from a trans-generational point of view, studies on the transmission of traumatic conditions across generations (Bohleber, 2007; Faimberg, 2005) can demonstrate that enactments may cross disregard the boundaries between generations that are also places of links and largely unconscious narcissistic pacts (Aulagnier, 1975; Kaës, 2005).